Ceiling fans primarily have blades that are attached to the motor housing brackets by multiple screws and the likes. Screwing the blades onto a ceiling mounted motor is not only difficult to accomplish, but results in most ceiling fans in the market place having visible screws that are unsightly. Furthermore, the underside location of the fastener screws detract from the appearance of the ceiling fan itself. Another problem is from the ceiling fans having to run under continuous vibration conditions where the screws can loosen causing the blades to be accidentally released and result in damages to surrounding property and people in the vicinity.
Furthermore, ceiling fan blades need to be cleaned to remove dirt and dust buildup. Current techniques have relied on manually holding brushes to the blades themselves which inherently tires the muscles in the cleaner""s neck, shoulders, arms and hands. This messy cleaning with brushes causes the dirt to fall on both the cleaner and furniture and flooring below the fan.
Attempts have been made at changing the attachment methods for the blades but still fail to overcome all the problems presented above. U.S. Pat. No. 4,884,947 to Rezek describes a cover for covering the blade to motor connections but still uses screw fasteners that have the problems described above. U.S. Pat. No. 5,180,284 to Monrose III et al. is entitled a xe2x80x9cDetachable Blades for Ceiling Fansxe2x80x9d and U.S. Pat. No. 5,433,585 to Yan has a removable pin connection for ceiling fan blades, but each of these patents still requires screw on brackets for both the motor housing and the blades. Similarly U.S. Pat. No. 4,396,352 to Pearce and U.S. Pat. No. 5,520,515 to Bailey et al. describe pitch adjustment attachments for ceiling fans but also still require screw on brackets between both the motor housing and the attached blades. A still further problem of many of these detachable ceiling fan type blades is that natural centrifugal forces of the spinning fans increases the chances of dislodging the blades.
Thus, the need exists for a solution to the above presented problems with the prior art.
The first objective of the present invention is to provide detachable blades for ceiling fans that are easy and quick to install.
The second object of this invention is to provide detachable blades for ceiling fans that allow each blade to be locked in place to the motor housing.
The third object of this invention is to provide detachable blades for ceiling fans that are adaptable to standard ceiling fan blades.
The fourth object of this invention is to provide detachable blades for ceiling fans wherein the centrifugal force of the fans actually locks the blades in place.
A first embodiment of the detachable blade and mounting arm assembly for a ceiling fan includes a blade having a three triangularly arranged keyhole slots at one end, and a ceiling fan motor connected mounting arm having an opposite end with three flat top shaped fasteners so that the keyholes are positioned over the the flat top shaped fasteners and locked by the longitudinal slot portions of the keyhole slots, after which a spring clip holds the position of the blade to the mounting arm. Optionally, a gasket can be inserted between the blade and the mounting arm.
A second embodiment is similar to the first but includes a decorative cap cover with an upward projecting fastener having expandable tips for being inserted within the keyhole slots of the blade and snappably attach into mating through-holes on the mounting arm.
A third embodiment has a slot in the end of the ceiling fan mounting arm for receiving a protruding end of the blade, the protruding end having angled corner edges. Spring loaded pistons rods in the mounting arm which face one another can fit into mateable grooves in the protruding end of the blade. The rods can be manually moved back to release the blades by handles.
A fourth embodiment has a single planar blade with an end having a slot. The mounting arm has an end with two parallel plates separated from one another by a central housing having back to back spring loaded piston rods. Passing the slotted end of the blade around the central housing so that the piston rods expand into grooves within the interior walls of the slot opening of the blade. Overhanging portions of the parallel plates further support the sides of the blade about the slot. Latch handles attached to the piston rods allow a user to manually move the piston rods against their respective springs to release the blade from the mounting arm.
A fifth embodiment has a single planar blade with an end having a slot with grooved interior walls. The mounting arm has an end with a top plate having uneven sides separated from a substantially rectangular bottom plate by a central housing having a spring loaded piston rod. The slotted end of the blade is positioned over the top plate so that the sides of the slot can abut against the bottom plate. Pulling the blade away from the mounting arm causes the piston rod to expand into a groove within the interior wall of the slot opening of the blade. The grooves and overhanging portions of the top plate and bottom plate prevents centrifugal forces caused from spinning the blade to dislodge the blade. Overhanging portions of the top and bottom plates further support the sides of the blade about the slot. A latch handle attached to the piston rod allows a user to manually move the piston rod its spring to release the blade from the mounting arm.
Further objects and advantages of this invention will be apparent from the following detailed description of a presently preferred embodiment which is illustrated schematically in the accompanying drawings.